Anesthesia apparatus



y 1968 5. K. PORTER 3,385,578

I ANESTHESIA APPARATUS Filed Sept. 28, 1966 l0 l8 r -54 5 58- 1 Tx Q1 52 2 t IQ 2 M ,34 Q Q 56 24 40 FIG. 2

FIG. I

INVENTOR GARY K. PORTER BYMMUM ATTORNEYS United States Patent 3,385,578 ANESTHESIA APPARATUS Gary K. Porter, Hatboro, Pa., assignor to Fraser Sweatman Incorporated, Bulfalo, N.Y., a corporation of New York Filed Sept. 28, 1966, Ser. No. 582,683 4 Claims. (Cl. 261-122) This invention relates to anesthesia apparatus and more particularly relates to a vaporizer for mixing the vapor of a volatile liquid anesthetic agent such as ether with a gas vehicle such as oxygen.

Vaporizers for mixing volatile liquid anesthetics with a gas are well known to the art. With the heretofore known devices the patient is subjected to a substantial risk of series harm resulting from the overfillin-g of the liquid anesthetic into the vaporizer causing an overflow through the outlet conduit leading to the patient. It is one of the main purposes of this invention to solve this problem by providing a novel vaporizer having means which automatically limit the level of the liquid anesthetic when the vaporizer is charged therewith.

The invention and its operation will be clarified by a reading of the following description in conjunction with the drawings in which:

FIGURE 1 is a vertical sect-ion of a vaporizer in accordance with the invention; and

FIGURE 2 is a horizontal sect-ion taken on the plane indicated by the line 22 in FIGURE 1.

A vaporizer 2 in accordance with the invent-ion has a met-a1 tank 4 provided with a threaded gas inlet opening 6 for the reception of a gas supply line (not shown) and a gas-vapor threaded discharge opening 8 for connection to a discharge line (not shown). A cap 10 is threadably secured to the upper open end of tank 4 as indicated at 12. Cap 10 is provided with a large threaded fill opening 14 in which is removably secured a threaded plug 16. Gasketing 18 is provided between cap 10 and tank 4 and gasketing 20 is provided between plug 16 and cap 10. A drain opening 24 is controlled by drain valve 26.

A metal canister 32 is mounted within tank 4 with its extended neck 34 pointed downwardly. Neck 34 passes through a flanged collar 36 mounted in a porous ring 38 of, for example, s-intered metal which rests on :an O-ring 40 and overlies a recessed portion 42 in tank 4. Ring 38 is such that it will permit the passage of a gas such as oxygen with little resistance and will cause the gas to emerge as fine bubbles. Suitable sintered metals are known to the art with a typical commercially available one being Porex produced by the Moraine Products Division of General Motors Corporation. Plate 38 is held down by a compression coil spring 44 which surrounds neck 34 and extends between collar 36 and canister 32.

A ring 48 is fixedly secured to the upper end of canister 32 as viewed in FIGURE 1 and is forced upwardly against cap 10 by the action of spring 44.

A gas inlet line 52 extends upwardly from opening 6 through neck 34 and into the upper end of canister 32 as viewed in FIGURE 1. Conduit 52 is spaced from neck 34 permitting the gas discharging into canister 32 from conduit 52 to pass downwardly between conduit 52 and neck 34 into recessed portion 42.

A conduit 54 extends downwardly through canister 32 to a point slightly below the desired liquid level indicated at 56, albeit the lower end of conduit 54 could be carried down lower. A conduit 58 extends from a point Within ring 48 downwardly through canister 32 to the desired liquid level 56. It will be noted that ring 48, cap 10' and canister 32 in eifect form a chamber 60 with conduit 54 extending downwardly from the bottom chamber 60 and the conduit 58 extending downwardly from a point sub- 3,385,578 Patented May 28, 1968 stantially above the bottom of chamber 60. Conduits 54 and 58 are secured to canister 32 by brazing or the like.

OPERATION In order to fill the vaporizer 2, plug 16 is removed and the liquid anesthetic agent is poured through opening 14 into chamber 60. The liquid runs downwardly through conduit 54 through canister 32 and into tank 4. As liquid passes downwardly through conduit 54 the displaced air pass-es upwardly through conduit 58 into the upper part of chamber 60 and out opening 14, it being appreciated that this is the only escape route for the air when openings 6 and 8 are connected to a gas inlet and a gas-vapor discharging line respectively. When the liquid rises to the level indicated at 56 air can no longer flow through conduit 58, and hence the flow of liquid into tank 4 ceases thus preventing charging more liquid into tank 4 than is desired and positively preventing the possibility of liquid anesthetic from passing out through conduit 64 which connects the upper part of tank 4 to discharge opening 8. With plug 16 replaced in opening 14, the vaporizer 2 can now be operated by pas-sing gas, for example, oxygen through conduit 52 from whence it passes downwardly into recessed portion 42 and thence upwardly through sintered metal ring 3-8 and through the liquid anesthetic in the form of bubbles to facilitate the vaporization thereof. The gas-vapor mixture passes upwardly in tank 4 to enter conduit 64 and thence pass to the exterior of the vaporizer.

The cleaning or replacing of Sintered ring 38 is very readily accomplished by simply removing cap 10 which permits canister 32 to be pulled out of tank 4. Sintered ring 38 may then 'be lifted out directly. This simple construction facilitates cleaning and replacement of parts.

It will be understood that the above described embodiment is merely by way of illustration and is not intended to be limiting.

What is claimed is:

1. A vaporizer for mixing the vapor of a volatile liquid anesthetic agent with a gas vehicle comprising:

a tank to contain the liquid anesthetic agent having an opening in its upper end,

means for passing bubbles of a gas through the liquid anesthetic agent,

conduit means having an inlet end in said tank and discharging to the exterior of the vaporizer to provide for the discharge of the gas vapor mixture from the vaporizer, and

means for preventing overfilling of the tank comprising means forming a chamber in the tank communicating wit-h said tank opening,

an air conduit extending downwardly from a point within the chamber and above the bottom of the chamber to the desired liquid level in the tank; and

a liquid fill pipe extending from the bottom of the chamber downwardly at least as far as the air conduit.

2. A vaporizer for mixing the vapor of a volatile liquid anesthetic agent with a gas vehicle comprising:

a tank to contain the liquid anesthetic agent having an open upper end,

closure means removably secured to said upper end and having a fill opening, closure means removably secured to the fill opening, a porous ring spaced from the bottom of the tank below the operating level of the liquid anesthetic,

an inverted canister in the tank having its neck extending down through the center of the porous ring,

means to supply a gas to the canister and to cause the gas to flow upwardly through the porous ring,

conduit means having an inlet end in the upper portion of the tank and discharging to the exterior of the vaporizer to provide for the discharge of the gasvapor mixture,

3 4 means mounted on the exterior of the upper end of the References Cited canister to form with the canister and the first mentioned closure means a chamber below the fill open- UNITED STATES PATENTS an air conduit extending downwardly from a point 5 156949 11/1874 Rush 261-17 above the bottom of the chamber and through the 2,342,602 2/1944 Reitz 128138 canister to the maximum desired liquid level in the 2,437,526 3/ 1948 Heidbrink et al. 261-121 XR ltanlc 23d t d d a Cu f th b H 2,485,739 10/1949 Johnstone 261-122 a lqlll pipe ex en mg ownw r y rom e o om 4 of the chamber and through the canister at least 10 262J014 12/1952 Kloth 261-121 as far as the air conduit. FOREIGN PATENTS 3. A vaporizer in accordance with claim 2 having compression spring means urging the porous ring downwardly 614,143 2/1961 Canadaand the Canister p y- 640,274 4/1962 Canada.

4. A vaporizer in accordance with claim 3 in which 15 the means to supply a gas includes a conduit passing HARRY THORNTON, Prinmry Examiner. upwardly through the center of the camster neck and spaced therefrom. E. H. RENNER, Assistant Examiner. 

1. A VAPORIZER FOR MIXING THE VAPOR OF A VOLATILE LIQUID ANESTHETIC AGENT WITH A GAS VEHICLE COMPRISING: A TANK TO CONTAIN THE LIQUID ANESTHETIC AGENT HAVING AN OPENING IN ITS UPPER END, MEANS FOR PASSING BUBBLES OF A GAS THROUGH THE LIQUID ANESTHETIC AGENT, CONDUIT MEANS HAVING AN INLET END IN SAID TANK AND DISCHARGING TO THE EXTERIOR OF THE VAPORIZER TO PROVIDE FOR THE DISCHARGE OF THE GAS VAPOR MIXTURE FROM THE VAPORIZER, AND MEANS FOR PREVENTING OVERFILLING OF THE TANK COMPRISING MEANS FORMING A CHAMBER IN THE TANK COMMUNICATING WITH SAID TANK OPENING, 